In recent years, it has become popular to provide musical concerts to large audiences, which audiences will not fit into standard concert halls or theaters because of space limitations. In the case of popular bands or musical performers, such as rock and roll bands or country and western singers, such performances have been provided in large sports arenas, such as baseball, football, or soccer fields, or other spacious outdoor facilities, including beaches or pastures. In order to provide a stage for the set-up of musical instruments and for providing a platform for the performers, such stages had to be constructed on-site from the ground up. Sports facilities, pastures, and beaches which can accommodate the large crowds attending the performances, are not normally equipped with the type of permanent covered stage from which the performers' equipment, including musical instruments, amplified speakers, video screens, lights, pyrotechnics, and other special effects, can be suspended and displayed. Further, because of the sensitivity of much of the equipment, including complex electronic lighting, amplifiers, speakers, video equipment, and the like, to weather conditions, the modern stages must be provided with adequate stable and secure roof coverage. In order to accommodate the complete visual effect of the performance and to allow all aspects of the performance to be viewed from the large audience, the roof must be spaced a substantial distance above the stage platform.
In the past, stage roofs have been constructed with the expenditure of much time and effort using standard building or scaffolding techniques, which to a large extent required extensive bolt tightening or clamping during assembly of the support structure and stage walls. There was a corresponding bolt loosening and clamp loosening during disassembly. Many of the roofs had to be constructed using cranes and workmen atop of the scaffolding or stage walls for long periods of time. Complex construction procedures at the top of the walls were dangerous and time consuming.
In recent years, it has been found that roof assemblies could be more simply and more safely constructed at ground level or at a stage platform level and then raised to above the ground or platform suspended from the top of scaffolding with steel cables. Such construction was less complicated and less time consuming, but nevertheless, necessarily resulted in a less stable roof configuration due to the flexibility of the suspension cables. Excessive tension in the cables, in order to reduce their flexibility, could cause dangerous overloading both of the cables, as well as the stage walls or scaffolding from which the cables were supported.